Maggie, 75mm, TB, and 730 RWHP...
 

Finally got a chance to get back on the dyno last week with the 75mm pulley and an upgraded 103mm throttle body from Nick Williams.

Attachment 857729

While Magnuson hasn't released the new throttle adapter for the 103mm yet (it's in process), it didn't take too much work to modify the original adapter.

Attachment 857730

Installation was a breeze, it simply bolted right in place and everything fit without any complication.

Attachment 857731

Surprisingly enough even the Magnuson rubber duct was able to stretch over the larger TB without too much problem.

So the current modification list for this power level is as follows:

• Maggie Heartbeat SC with 75mm pulley
• 103mm Throttle Body
• Lingenfelter Big Bore HPDI fuel pump
• LT4 injectors
• ZL1 intank fuel pump.
• AEM water injection system
• Rotofab CAI
• Borla Cat Back
• MS109 unleaded (105 octane)
• Otherwise engine is all stock including exhaust manifolds and catalysts.

Attachment 857732

The TB upgrade added about 13 RWHP at this level. I still have some tuning to do before I'm ready to go back to the track in the mid RPM range and maybe raise the limit a bit higher as it's still pulling hard at 6400RPM. If my calculations are right, with 730 RWHP there's a good chance we'll be able to see a single digit pass next time out. :)

Sounds solid. But why did they use STP correction?

I've been in contact with Mike a couple times a week and he's been keeping me up to date on his testing. Last I talked to him he was about 30 hp short of where he is now. All I can say is wow, that Nick Williams TB and finally the 75 mm put down some serious RWHP. Nice job Mike and glad you found a belt for that 75 mm pulley. He's a tuning master for sure.

Very Nice results.. and I believe you are correct a high 9's should be achievable with a good 60'

Great combo, if I wasn't going ProCharger this is the way I would go

Great numbers. Do you know the kpa?

I agree that 9's are coming. I'm working on getting into the 10's this weekend. Mine made 544/559 and going to run 93 on a couple runs and then switch to 109 with Mike's vp tune. (not his current tune) It should be worth 40hp at the wheels, expecting low 1.50 60ft times and upper 120's for mph. I know Mike wants to get back to the track soon to test his combo. It should be stellar.

I continue to be impressed with this setup. Particularly the fact that you're still running stock exhaust.

If I do headers it will be the mid tubes like I had on my SCg8, Mike hasn't added headers yet but headers are in his future. Its very impressive I think and can't wait to see it run on the Power Tour in St louis.

Mike, have you found a good source for different size belts? I could be looking for a longer belt in the future.

Well Done Mike, I seen 9s for sure.

Heck if you spin it 6600 you might see 750

Ted.

Yep I'm in! That's awesome power with a stock cam & no headers!!

I've been looking at that 103mm throttle body just never knew what it would take to make it work. I didn't know Magnuson was making something.

What power is feasible with this type setup but in a state which only offers 91??

OP is in the same state as you. He is probably getting the MS109 either at a race track or a fuel dealer.

My tune right now is a 91 octane tune that Mike sent me since there is no 93 in Cali. Mine made 544-559, I have no other mods. I'm expecting an additional 40-50 hp when I switch to ms109 this weekend after a couple runs on 93 octane for my baseline